1. Field of the Invention
This invention relates to molding plastic materials of different kinds and relates particularly to molding concrete bricks having an antique appearance.
2. Description of the Prior Art
Heretofore many efforts have been made to provide a coating of coloring material on one or more surfaces of a brick or tile of ceramic, clay, concrete or other base material and these efforts have included painting or spraying the coloring material on the base material, forming a liquid mixture of the coloring material and pouring such mixture on the base material, and coating the vertical walls of the mold with coloring material before introducing the base material. In some cases the coloring material has included several colors which are applied indiscriminately, while in other cases different colors have sharply defined edges when applied to the base material. These prior methods and structures have been time consuming since they required substantial hand operations for mixing, painting or spraying one or more exterior surfaces of the base material, and have been wasteful of the coloring material when the walls of the molds have been coated.
Some examples of the prior art which utilize painting or spraying of the base material are U.S. Pat. No. 1,638,108 to Barnes-Thomas and U.S. Pat. No. 3,939,238 to Salts. Some examples of the prior art which coat the walls of a mold are U.S. Pat. Nos. 1,704,193 to Hoffman; 1,739,370 to Stead; 1,984,059 to Dandini; 2,020,137 to Damhorst; 3,425,105 and 3,621,086 to Gulde.